Best eSIM for Thailand: Provider Comparison & Costs 2026

EU roaming has trained a lot of people to expect mobile data abroad to just work. You fly to Mallorca, the phone connects, your data allowance comes out of your normal plan. No surcharge, no tapping through menus, no nasty line on next month's bill.

Thailand works differently, and the difference is legal rather than technical.

The regulation covers a fixed set of countries, and Southeast Asia isn't in it. For anywhere outside that set, German carriers sell you separate bundles that you have to book yourself. Book nothing and you fall back either on an automatic spending cap or on per-megabyte pricing, and honestly neither is somewhere you want to be. That's where the actual decision starts, and it's much better made before departure than at the baggage carousel.

There are three routes. Booking a bundle with your existing carrier. Buying a travel eSIM online before you fly. Or walking up to a counter in Thailand and picking up a local prepaid card. All three work. They cost wildly different amounts.

This is the part no provider blog does, because no provider has any reason to want you comparing the numbers directly. Everything below comes from the relevant official pages, retrieved on 9 August 2026. The scenario: 10 days, one device, ordinary use, occasional streaming.

Telekom offers a DayFlat unlimited for Thailand at €9.95 per day (as of 9 August 2026, Telekom). Ten days, booked ten times, €99.50. That's the most expensive path in this table, and it isn't close.

Vodafone's ReisePaket World runs at €9.99 per day or €34.99 per week, and the provider lists Thailand as covered (as of 9 August 2026, Vodafone). Take the weekly bundle and add the remaining three days individually and you land at €64.96. Forget the weekly option, book daily out of habit, and you're at €99.90, which is basically Telekom money. One tap of difference, thirty-five euros of difference.

And the gap between the two halves of that table isn't a rounding error. Even the priciest unlimited eSIM here, Holafly at US$36.50, sits below every carrier bundle. Nomad at €13.85 comes to roughly a seventh of the Telekom bill.

There's a real point in the carrier's favor, though. With a carrier bundle your German number stays live, texts and calls included, nothing to reconfigure. Travel eSIMs are almost always data-only. Your home number can stay reachable if your handset does dual SIM, but incoming texts abroad still bill at your home tariff's rate. If your job depends on being reachable, or your bank sends one-time codes by SMS, that's worth checking before you buy anything.

This is the single most useful thing we turned up while researching this piece.

O2's Roaming Plus World covers Thailand: €14.99 a month, currently 4 GB. That's a promo through 31 August 2026, after which the regular allowance of 2 GB applies (as of 9 August 2026, o2online.de). For a typical 10-day trip, that beats every other option above.

The catch is the data cap, not the price. 4 GB, soon back to 2 GB, covers maps, messaging and a handful of photos, but not days of streaming or working from a hotel room. If your data needs are modest, O2 gets you through cheaply. If you need more, an unlimited eSIM like Nomad is still the safer call.

If you're with O2, it's worth checking the linked page yourself before you fly. Country lists and promo volumes like that do change.

We haven't tested any of these. Nobody here went to Thailand for this article, ran a speed test, or burned through a plan. What follows is published pricing and provider claims retrieved on 9 August 2026, plus the places where those claims struck us as incomplete. So there's no "winner" section. We'd have nothing to base one on.

Nomad

The cheapest unlimited plan in our comparison: 10 days unlimited from €13.85 (as of 9 August 2026, Nomad). That's well under the better-known names, and if price per day is genuinely your only criterion, the decision is more or less made here. The catch, as always, hides inside the word "unlimited". More on that below.

Airalo

The best-known name in travel eSIMs, with more than 200 destinations. For Thailand: 10 days unlimited from €28.00 (as of 9 August 2026, Airalo). What the premium over Nomad buys is reach. If Thailand is one stop before Vietnam, Cambodia or Japan, you keep everything in a single app instead of installing a new one per country. For a Thailand-only trip that argument does nothing for you.

Holafly

The most expensive option in the table at US$36.50 for 10 days unlimited (as of 9 August 2026, Holafly). Holafly leans hard on the unlimited-data angle and markets it aggressively in a lot of countries. On pure arithmetic you're paying about two and a half times Nomad for the same trip length. Whether the support or the network partner justifies that, we honestly can't say, because we didn't test it.

aloSIM

The interesting one for people who barely use mobile data: 1 GB for 7 days from US$3.50 (as of 9 August 2026, aloSIM). For Google Maps, WhatsApp, a handful of booking confirmations and a translation app, that's often plenty. The provider markets it that way too, as a basic tier rather than an all-rounder. If you're on hotel and café wi-fi most of the time anyway, this gets you through a week for less than an airport coffee.

Saily, with a caveat

Saily gets recommended a lot in German media and turns up in nearly every comparison. We're still not printing a price table for it, though it's probably competitive on price. The provider's site blocked our request, so everything we have is second-hand. Saily's own website advertises Thailand plans starting around US$3 for 1 GB, but we haven't verified that independently. Treat the figure with appropriate suspicion and check the site yourself before buying.

What "unlimited" actually means

No provider selling an unlimited plan gives you full speed indefinitely. They all run a fair-use policy: you get high speed up to a certain daily volume, and after that you're throttled, often to a rate where maps and messaging still work and video streaming doesn't.

The specific thresholds and throttle speeds floating around online come from provider marketing copy rather than from any measurement we could trace, so we're not printing a number for them. The takeaway is simpler anyway. "Unlimited" means an unlimited number of megabytes, not unlimited speed. If you're planning to work from a hotel room in Chiang Mai or watch a series in the evenings, the tariff details are worth reading properly instead of trusting the word on the product page.

The old-fashioned route, and it isn't dead. At Suvarnabhumi airport the Thai carriers have counters right in the arrivals hall, and the tourist plans are cheap: True sells a Tourist INFINITE card with 8 days unlimited for 449 THB (as of 9 August 2026, True).

The difference against an eSIM isn't the price, it's the hassle. A local Thai SIM has to be registered with a valid passport under NBTC regulations, and you can register at most three cards per person per brand (same source, as of 9 August 2026). In practice: queue, dig out your passport, fill in a form, wait, swap cards, then find somewhere safe for your German SIM.

What you get in return is a Thai phone number. Sounds trivial until you need to ring a Grab driver, contact a guesthouse out in the provinces, or book a tour where someone calls you back.

One thing we're deliberately leaving open. Thailand has been tightening its SIM registration rules in recent years, including moves towards biometric capture. Whether those rules will reach eSIM profiles from foreign providers, we couldn't establish properly, since the one source discussing it wasn't reachable. What holds today: buy a data eSIM online in advance and you won't be showing a passport at any counter in Thailand. That isn't a guarantee for the years ahead, and no one selling it as permanent knows better.

Here's where it gets awkward, because this is where everyone else pretends to have data.

We don't have any. Speed test figures for AIS, TrueMove H and the former dtac networks sit behind paywalls, and the freely available numbers contradict each other. What several independent sources do agree on is a rough tendency: AIS is generally regarded as having the strongest coverage away from the cities, so on the islands and out in rural areas. In Bangkok, Chiang Mai, Phuket and the other tourist centres, every network works well enough that the choice barely matters.

Consider that orientation rather than measurement. If you're heading to a smaller island or somewhere genuinely remote, searching a current forum thread for that specific place will serve you better than a coverage map lifted from a comparison article. Travel eSIMs also connect to one fixed partner network you can't choose, so check the tariff details if that matters, or go local instead.

The fastest check takes about ten seconds. Type *#06# into the phone app. If an EID appears alongside the IMEI, your device supports eSIM. You'll also find it in settings under mobile or cellular, where depending on the manufacturer it's called "add eSIM" or "add mobile plan".

We're not printing a model list. The official overviews from Apple and Google shift with every device generation, so a list here would be wrong within months. Check there, or run the test above.

A second thing gets missed a lot. A handset financed through a carrier and not yet unlocked can reject third-party eSIM profiles even though it technically supports eSIM. If your phone came bundled with a contract, the time to sort out the SIM lock is at home, not at the gate.

Short, and kept separate, because people conflate these constantly. Regardless of which SIM route you take, everyone entering Thailand has had to complete the free Thailand Digital Arrival Card since 1 May 2025, no earlier than 72 hours before arrival (as of 9 August 2026, U.S. Embassy Bangkok). It replaced the old paper TM6 form.

It has nothing to do with mobile connectivity. The TDAC is an immigration entry form; SIM registration is a telecoms regulator requirement. Both are digital and mandatory, which is exactly why travel forums keep mixing them up. So you still need the TDAC even if you arrive on an eSIM and never see a SIM counter.

No winner, since we don't have one, by trip type instead:

• Short trip, mostly wi-fi: a small data plan, aloSIM for example

• Ten days to three weeks: an unlimited travel eSIM, usually Nomad

• Need a Thai phone number: local SIM, passport at the airport

• On O2: Roaming Plus World at €14.99/month covers light use, otherwise eSIM

• Working or streaming abroad: check the fair-use terms first

Short trip up to a week, mostly on wi-fi. A small data plan covers it. aloSIM at US$3.50 for 1 GB handles maps, chat and booking confirmations, and between hotel wi-fi and café wi-fi that's often all you touch.

Ten days to three weeks, ordinary use. An unlimited travel eSIM wins here, and not narrowly. Nomad at €13.85 for 10 days is the cheapest option we could confirm. Airalo costs more but is the more practical pick if Thailand is one leg of a longer trip through Asia.

You need a Thai phone number. Then it's a local SIM, passport in hand, queue at the airport. No eSIM solves that problem for you.

You're on O2. Roaming Plus World covers Thailand for €14.99 a month, currently with 4 GB, plenty for maps and chat. For heavy streaming or working on the road, an unlimited eSIM is still the more reliable pick.

You plan to work or stream abroad. Reading the fair-use terms of whichever plan you fancy is worth the five minutes, and expect throttling once the daily high-speed window is gone. If your income depends on the connection, a local SIM on a named network is the more reliable bet.

Whichever way you go, sort it out before you fly. The one genuinely expensive mistake in this whole story is doing nothing and switching roaming on in Bangkok.